KENNEBUNKPORT, Maine — As she walked her yellow Lab along a frigid Goose Rocks Beach Thursday, Pam Reynolds surveyed the broad, curved stretch of sand and sadly shook her head.

Sections of her neighborhood beach, a summer treasure for generations and a jewel of Maine’s southern coast, were declared private property this week in what could prove to be a far-reaching court decision. The prospect of losing access to parts of the lovely shore and having its 2-mile stretch interrupted was devastating.

The decision, handed down Tuesday by the state’s Supreme Judicial Court, sided with 29 beachfront property owners who asserted exclusive rights over the beach “down to the mean low-water mark,” even though the beach has been used by the public for decades.

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In Kennebunkport, a popular summer vacation spot with a closeknit year-round community, some of whom have generations-old roots in the town, the long-running dispute has been divisive, fracturing a community already torn over gentrification and casting a cloud over a place seen as a peaceful escape.

“It’s been a blemish,” Reynolds said. “It’s ruined that peace of mind.”

The town argued that it has long maintained the beach — posting police officers there, repairing its seawall, and spraying for mosquitoes — and that its longtime public status overrides private property concerns.

“There’s a long history of public use,” said the town’s lawyer, Amy Tchao. “The town has made significant expenditures.”

The court found otherwise, ruling that such tradition was not enough to overcome the rights of property owners.

Tchao said the decision overturned precedent established in a similar case in nearby Wells and could have an impact on other coastal property claims.

“It’s a radical departure,” she said. “This court has said that even walking in the intertidal zone is presumed to be by the permission of the landowner.”

While residents voiced anger and frustration over the ruling, a fairly large portion of the beach remains open to the public, about half of it by Tchao’s estimate. Some property owners reached an agreement with the town last summer that allows public access to their portions of the beach; other sections are owned by the town or a conservation trust.

But with the ruling, some worry that property owners who have been annoyed by the public use may enforce their newly named rights and move to bar access to their portion of the beach.

“Now that they’ve won, all bets are off,” said Wesley Phillips, 71, who walks the entire length of the beach most days.

Phillips said he wasn’t sure what he would say if he was stopped by a homeowner, but that it wouldn’t likely be printable. “It’s a shame,” he said.

The lawyer for the property owners could not be reached for comment.

Opinion on what prompted the suit was divided. Some said the property owners were probably annoyed by the influx of people on busy days, and the traffic that clogs area streets.

“I think they just get irritated by the crowds,” said John Bain, 63, a longtime resident who visits the beach on even the coldest days.

But many residents said that relatively few people go to that end of the beach, assuming it is private because of the lack of parking. And those who do use the beach are generally well-behaved, residents said.

“It’s one of the nicest beaches in Maine,” Bain said. “It should be for everyone to enjoy. If people can’t, they are going to be upset.”

The legal battle, which began in 2009, has divided the community, residents say. Many owners of homes off the beach filed counterclaims, pitting neighbors against neighbors.

“I’m amazed it’s come to this,” said Reynolds, who lives near the beach. “The idea of sealing this off, it’s ludicrous. Hopefully common sense and decency will prevail.”

Residents said the beach is popular with families and can handle large crowds, especially at low tide. Most beachgoers are from the area, though the beach attracts some daytrippers. Neighbors said the scene is never rowdy, even on the busy summer weekends, and that the crowds overwhelmingly gravitate toward the town-owned section of the beach.

Others say owners knew when they bought their property that they overlooked a popular public beach.

“C’mon,” Bain said. “They knew what they were in for.”

Even on a day when the wind whipped off the water, a number of residents walked along the beach, and many said they worried how long they would be able to.

One woman, who often takes her son to the beach, said she was saddened by the ruling.

“This isn’t just a beach,” she said. “It’s as close to heaven as you can get.”

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